IFX_FOLDVIEW configuration parameter

Use the IFX_FOLDVIEW configuration parameter to enable or disable view folding. For certain situations where a view is involved in a query, view folding can significantly improve the performance of the query. In these cases, views are folded into a parent query instead of the query results being put into a temporary table.

onconfig.std value
IFX_FOLDVIEW 1
values
0 or Off = Disables view folding.

1 or On = Default. Enables view folding.

takes effect
After you edit your onconfig file and restart the database server.
When you reset the value dynamically in your onconfig file by running the onmode -wf command.
When you reset the value in memory by running the onmode -wm command.

Usage

The following types of queries can take advantage of view folding:
  • Views that contain a UNION ALL clause and the parent query includes a regular join, HCL Informix® join, ANSI join, or an ORDER BY clause
A temporary table is created and view folding is not performed for the following types of queries that perform a UNION ALL operation involving a view:
  • The view has one of the following clauses: AGGREGATE, GROUP BY, ORDER BY, UNION, DISTINCT, or OUTER JOIN (either Informix or ANSI type).
  • The parent query has a UNION or UNION ALL clause.

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